Tire repair plug



Nov. 10, 1931. A. A. HAWKINSON I TIRE REPAIR PLUG Filed Jan. 51. 1929 2 Sheets-Sheet 1 j jwmz a/ Ari/2.711 14. jinn i030];

NOV. 10, 1931. w so 1,831,000

TIRE REPAIR PLUG Filed Jan. 51, 1929 2 Sheets-Sheet 2 a j Www W Patented Nov. 10, 193l UNITED ARTI E UR A. HAWKINSON, MINNEAIBOLIS, MINNESOTA 1 w na e rim application iiled ilfanuary 3}, Serialfljo. 3,37.

This invention relates to plugs for repairing tire casings, and more particularly to the type of plug wherein a metallic quill or stem is used .for drawing the plug through plug will elongate the plug and decreaseits diameter so that it may be drawn through the puncture and then, when released, the plug will longitudinally shorten and become diametrically enlarged to tightly close the puncture, all as will hereinafter more fully app I To accomplish the results above generally t d, t is e i z tha h quil 9f re atively small diameter should be attached and anchored only to the reduced end port n Of the Pl g: Th r i iion" one Pl a is pt t l th e i iii ill there fore, in all cases, be of Very great-er diameter than that of the stemsecured to the n h r o or f th p nct f tp be elqsed thereby and then, of course, it tollows that the inscrtion of theplug into the puncture can be accomplished only bypulling and elongating ih 'pl and her by de e iia its diameter so that it can be drawn into and through the puncture. w

The plug proper may take difierent forms,

but in all cases its body portion, that is,that portion thereof that is to fill the puncture, will be normally in an undistorted condition and free for elongation and decrease in diameter to its elastic limit by stress put thereon in the act of pulling the plug through the puncture.

The invention is illustrated in the accompanying drawings, wherein like characters indicate like parts throughout the several views.

Referring to the drawings:

. 9 Fig. 1 shows the tire casing in transverse section and one of the improved plugs in position to be drawn into and through the puncture "-lFigs. '2', 3, 4 and 5 are fragmentary views correspondingto Fig. l, but prpgressively OFFICE indicating steps in'thoperation of'applying I the plugto close a puncture;

' Fig.1 6 is an enlarged viewer the plug showing the same partly in side elevation and part- 1y maxim ection; H

ig f7 is section-taken on the line 7-7 Q g but showing the plug with or formation and Fig lZaiid' 13 re v e cerrespondins to Figs; 4 andf but showing theapplicati'ofi of Fig. 8 shows the plug before th t l i q l h been api l lthemed); r

Fig. 11 is a view corresponding to Fig. 6,

plug" of the form shown indet'ailin F 11.

' "The numeral liindicates the'fabric inner pertieii, a h'e numer l 1 the Outer 'riiblfii or tread portionof an ordinary tire. casing which casing is shown as having a puncture 16' I Th b dy 'l Plu whi h a s t aiy is 9f 'et be 1 s ii t ffQl im' sh e s l 2, 3, 4, nd p ev 'f lesl i h aimed 1 which forms a P us i s salled m sh c yp i. i. i

The quill or steml9 for drawing theflplug th ou h a p e is p ef r ly" fi rmfd tapered and hollow from a triangularnie tallic sheet 19. In the rolling or formation of h s q it is ve y t gh y presse 'and permanently anchoredonto the end 17- of the elastic plug body 17 therebyudiametrically reducing the saidend 17% to a'diameter very muchless than that of the normal diameter 3 of theplug, to wit: preferably to about oneap liedtefine e e th gri be w h Stein and the diametrically reduced end of the plug.

Fig. 1 shows the plug ready for insertion through the puncture 16 in the tire casing; Fig. 2 shows the plug initially started into the puncture; Fig. 3 shows the plug partly drawn into the puncture; and Fig. 4 shows the plug completely drawn into the puncture. By reference to Fig. 4:, it will be noted that the portion of the-plug that has been drawn? outward through the puncture,will naturally expand to substantially its normal diameter. After the plug is drawn to position, its

outer portion should be cut off at a point i greater expansion of the plug within the said outer portion. In view of this tendency toward greater expansion in the outer portion of the casing, it may be desirable, in some instances, to form the plug with an outward flare, as illustrated in Fig. 10, wherein the plug 20 is larger at its outer portion than its inner portion, or, otherwise stated, "is tapered toward its head 21. p

The plug 22 shown in Figs. 11,12 and '13 is formed wi hout a head proper, but is pre ferably'formed with a flaring inner end 23. The metallic stem 19 inthis form of the plug as in the plug previously described, is clamped securely onto the reduced outer end-22 of the plug 22. Fig. 12 shows the plug illustrated in Fig. 11, drawn into the puncture of the tire casing, and Fig. 13 shows the outer portion of the plug out off or severed from the compressed plug portion that fills the puncture. K

In all of the plug structures above described, there is an attached threading stem for drawing the plug through the puncture;

the stem is of such size that it will not increase the size of the puncture by stretching. tearing or distortion; the-stem which is first pro ected through the puncture may be grabbed with the hands or with pliers 'to stretch and reduce the diameter of the body of the plug and to pull the same through the puncture; and the body of the plug that is to close the puncture, is always left un- "covered' so that it will be drawn into the puncture only as it is properly decreased in diameter by stretching while in contact with the walls of the puncture so that upon release of the intensive stress on the plug, the

elastic plug body, by its own natural .ten- ,sion will become longitudinally shortened and 1 diametrically enlarged to the extent permitted by the surrounding walls of the'apertuie or puncture and said plug, will forrna perfect and very tight seal between the plug and the walls of the puncture. In actual practice, this plughas been found very highly eflicient for the purposes stated. The threading stem, someti1nes called a quill, may be made andapplied on the reduced end of the plug in any suitable way other than that above particularly described, for example, the quill may be formed by taking a metallic tube of sufiicient diameter telescoped over the normal unreduced end of the plug and then the quill can be reduced to proper size by compressing the same and the plug therein by swaging or rolling actions.

From the illustration and description above given, it is evident that the tubular stem or quill is connected to the body of the plug without cutting away or weakening the rubber of the plug at the place of connece tion, for in reducing the diameter of the end of the plug by the application of the stem thereto, the rubber is simply circumferen :ially reduced and therefore maintains in the reduced portion, substantially the same tensile strength as in the normal body of the plug. The tubular stem in the process of its contraction is simply pressed onto the end of the plug and the engaged end of the plug is reduced in diameter simultaneously with the stem by elongation which takes placeunder pressure. In this way also the best kind of a'frictional contact is made between the tubular metallic stem and the elastic rubber plug. By reference to Fig. 2. it will be noted that in the initial action of drawing the plug through the puncture,,the plug is s retche'd so that its diameter at the junction with the stem or quill is of approxi mately the same diameter, which greatly facilitates the drawing of the plug through the puncture.

' What I claim is:

A tire plug comprising an elastic plug body having a metallic inserting stem permanently applied to one end thereof, the portion of the elastic plug body thatis adapted to fill an aperture being exposed and normally in an undistorted condition so that it is free to be elongated and diametrically reduced to its elastic limit, and said stem being of very materially less diameter than the normal diameter of the portion of the j ARTHUR A. HAWKIN SON. 

